1. Field of the Invention
The present invention relates to a semiconductor device and a method for producing the same.
2. Description of Related Art
A high withstand voltage semiconductor device (a power device) to which a high voltage is applied is generally employed in the field of power electronics. The high withstand voltage semiconductor device includes a resistive element made of polysilicon, for example, as a passive element constituting an internal circuit along with active elements.
FIG. 14 is a schematic sectional view of a conventional high withstand voltage semiconductor device.
A semiconductor device 201 includes a P-type substrate 202. An element isolation film 203, made of an insulating material, partitioning an active region is formed on the surface of the P-type substrate 202. In the active region, various active elements (transistors, diodes and the like; not shown) are provided on the surface layer portion of the P-type substrate 202. A resistive element 204 is formed on the element isolation film 203. An interlayer dielectric film 205 is laminated on the P-type substrate 202, and covers the element isolation film 203 and the resistive element 204.
A wire 207 connected to an external power source and a wire 208 connected to another element (an active element) are arranged on the interlayer dielectric film 205 at an interval from each other. The resistive element 204 extends between a position opposed to the wire 207 and a position opposed to the wire 208 on the element isolation film 203. Contact holes 206 are formed between both end portions of the resistive element 204 in the longitudinal direction and the wires 207 and 208 respectively, to pass through the interlayer dielectric film 205 in the thickness direction. The contact holes 206 are filled up with contact plugs 209 made of a conductive material. Thus, the wire 207 is electrically connected to one end portion of the resistive element 204 through the corresponding contact plug 209, and the wire 208 is electrically connected to the other end portion of the resistive element 204 through the corresponding contact plug 209.